樟子松多酚和蛋白质的复合反应及产物性质

Polymerization and product characteristics of polyphenols of Pinus sylvestris var. mongolica barks and protein

将樟子松多酚分别与明胶和大豆分离蛋白进行复合,研究松多酚与蛋白质复合反应的优化条件,采用红外光谱和差式扫描量热法(DSC)对产物性质进行分析。结果表明:樟子松多酚-明胶复合反应的优化条件为多酚-明胶质量比为2∶1,温度40℃,时间30 min,p H 7,此条件下复合率达70.35%;樟子松多酚-大豆分离蛋白复合反应的优化条件为大豆分离蛋白-多酚质量比4∶1,温度30℃,时间20 in,p H5,此条件下复合率达47.21%,松多酚-明胶的复合率明显高于多酚-大豆分离蛋白的复合率(P<0.05)。红外光谱结果表明:樟子松多酚和蛋白质发生交联,引起O—H伸缩振动,在3 600~3 200 cm^(-1)产生强吸收,复合后O—H、N—H、C—H、S—H等基团明显变化。DSC结果表明多酚与明胶和大豆分离蛋白的复合使产物热变性温度提高。

Polymerization of polyphenols and protein is affected by muhiple factors. This study was designed to clarify the optimal polymerization conditions of gelatin and polyphenols from Pinus sylvestris var. mongolica, with soy protein isolate （SPI） as protein substrate. The characteristics of product were analyzed with infrared spectrophotometry and differential scanning calorimetry （DSC） , and our goal was to improve the polymerization rate. The results showed that： for polyphenols-gelatin polymerization, the optimal conditions were the mass ratio of polyphenols to gelatin 2： 1, reaction temperature 40 ~C , 30 - min duration and pH 7.0. Under these conditions, 70.35% of polyphenols were polymerized. For polyphenols-SPI polymerization, the optimal conditions were the mass ratio of SPI to polyphenols 4： 1, reaction temperature 30 ~C, reaction time 20 min and pH 5.0; in this case, 47.21% of polyphenols were polymerized. The polymerization rate of polyphenols-gelatin was significantly higher than that of polyphenols-SPI （P 〈 0.05）. IR spectroscopic results showed that polyphenols and proteins were cross- linked, resulting in the O--H stretching vibration and intensive absorptions were detected at the 3 600 - 3 200 cm-1. O--H, C--H, N--H, S--H and other groups had obvious changes after polymerization. The results of DSC showed that heat denaturation temperatures were raised after polymerization.